Answer:
Explanation:
velocity=s/t
given distance is 480 km we have to convert it into meter because the unit of distance is meter
1 km=1000 m
480 km=480000 m =4.8*10^5
1 hour= 3600 s
12 hour =43200 s
now velocity=s/t
v=4.8*10^5/43200
v=11.11 m/s
Physical forces because physical force can only move the box
Answer:
Its speed decreases.
Explanation:
When light enters into water, its speed decreases (as well as its frequency). This is the reason why refraction (the bending of light when it changes media) occurs.
This can be proven mathematically.
Given that the refractive index of water is 4/3, we know that refractive index is the ratio of the speed of light in a vacuum to the speed of light in another medium.
Therefore,
4/3 = (speed of light in vacuum) / (speed of light in water)
Speed of light in a vacuum is 3 * 10^8. Hence,
Speed of light in water is:
v = (3 * 10^8) / (4/3)
v = 2.25 * 10^8 m/s
As we can see, the speed of light decreases in water.
Answer:
C. Replacing one gas by another under the same conditions, has no effect on pressure.
Explanation:
Ideal gas:
A gas is treated as an ideal gas if temperature is high and pressure is low.
Kinetic energy for ideal gas given as
So when temperature of gas is increases then Average molecular kinetic energy will also increases.
The size of molecule is negligible as compare to the dimension of container. It mean that volume occupied by molecule is less as compare to the volume of container.
The between molecules is perfectly elastic.
Ideal gas equation
P V = m R T
So the option C is not always true.
